BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Talks.cam//talks.cam.ac.uk//
X-WR-CALNAME:Talks.cam
BEGIN:VEVENT
SUMMARY:How is mtDNA transcription regulated? - Professor Nils-Göran Lars
 son\, Karolinska Institute 
DTSTART:20221124T150000Z
DTEND:20221124T160000Z
UID:TALK183281@talks.cam.ac.uk
CONTACT:72232
DESCRIPTION:A single copy of mammalian mtDNA is compacted by binding of ~1
 000 copies mitochondrial transcription factor A (TFAM) to form the mitocho
 ndrial nucleoid. The compaction of the nucleoid varies\, and transcription
  has been reported to occur from its less compacted form. The TFAM-to-mtDN
 A ratio influences nucleoid compaction in vitro and in vivo\, but the mech
 anism controlling this regulation of compaction remains obscure. Transcrip
 tion initiation of mammalian mtDNA requires the bacteriophage-like mitocho
 ndrial RNA polymerase (POLRMT)\, TFAM and one additional factor\, whereas 
 the switch to transcription elongation requires that POLRMT interacts with
  a third factor. The transcription system in mammalian mitochondria is thu
 s very simple and distinct from the much more complex systems in the nucle
 us. We have performed a range of biochemical and genetic experiments in th
 e mouse and the results are consistent with a model where regulation of mt
 DNA gene expression is mainly dependent on posttranscriptional mechanisms.
  Furthermore\, our results argue that the synthesis of nucleus-encoded OXP
 HOS subunits is not closely correlated with the synthesis of mtDNA-encoded
  subunits. Instead\, proteolytic degradation of excess OXPHOS subunits see
 ms to adjust the balance so that the levels of nucleus- and mtDNA-encoded 
 subunits match when the OXPHOS complexes are formed. 
LOCATION:MRC MBU\, Level 7 Lecture Theatre\, The Keith Peters Building\, C
 B2 0XY
END:VEVENT
END:VCALENDAR